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necessary to account for thought and volition in the case of man, it is equally necessary in the lower animals. If our desires and volition, themselves uncaused in a physical sense, can fire a train of nervous energy which results in muscular activity, the same cause must exist wherever we find the same mechanism attended by the same result, else reasoning, as applied to objective existence, is utterly false. Or, to reverse the statement, if the desires and volition of the lower animals are simply attendant phenomena of nervous energy, what right have we, in man, to interpose a new element, where the facts to be explained are essentially the same? It is too late to deny the essential similarity of man and the lower animals; the rudiment of every faculty possessed by us is found in them. And these faculties are the same in kind-consciousness is consciousness, and thought is thoughtwhether exhibited in a man or a dog. But if you admit a spiritual element in the lower animals, where do the functions of matter end and those of spirit begin? How low in the order of nature will you go with this spiritual substance? Has a tadpole a soul? Does an amoeba, or a speck of undifferentiated protoplasm, enjoy the distinction of personal immortality? If one accepts the doctrine of evolution, when an organism in the course of development first begins to feel, then, presto, a new element appears, namely, soul. If one rejects this doctrine, one does not escape the difficulty, for there is a broad border land between sentient and nonsentient creatures, where the difference is so slight that it is impossible to draw the line with certainty; yet it is just this difference that culminates in man, and requires, we are told, a distinct element-a different kind of force-to account for, namely, spirit.*
* [ It is obviously true that all one knows of the Cosmos is predicated on phenomena, and that by phenomena one is informed as to states of matter, only; and yet it is equally obvious that outside of all this there is a vast region of the Unknowable in which the Ego, the conscious I, is the central figure. This something, call it by whatsoever name one will, is not force, it is rather the differentiating principle in matter-in nature. Force and matter, if one can conceive of them as distinct from each other, are but the instruments of its manifestation. Every one is conscious of a Self," and equally conscious of the existence of a "Not-self." This is a fact of feeling indissolubly woven into consciousness. It is absolutely inexplicable; and as Mr. Lewes forcibly says,
2d Series: VOL. VII.-NO. I.
Let us look at the matter from a different stand-point. Recent experiments upon the lower animals prove beyond doubt that many of the acts commonly considered voluntary, and which are certainly attended by consciousness, are in fact automatic, and are as well performed in the entire absence of consciousness or volition. Pflüger carefully removed from a frog the entire encephalon, leaving only the spinal cord. He then touched the thigh with acetic acid, to the application of which frogs are peculiarly sensitive. The animal thereupon rubbed the irritated part with the foot of the same side, apparently appreciating and localizing the irritation and endeavoring, by a voluntary effort, to remove it. The foot of this side was then amputated, and the irritation was renewed in the same place. The animal made an ineffectual attempt to reach the spot with the amputated member, and, failing in this, after some general movements, rubbed the spot with the limb of the opposite side. Here we have a series of acts, which are commonly considered the result of sensation and volition, as well performed in the entire absence of the brain. We have, in other words, proof positive that sensation and volition are not confined to the brain, nor to the mind, as ordinarily conceived, but are powers which may be exercised-nay, are exercised by the spinal cord and the medulla oblongata.
Again, remove the cerebral hemispheres from a pigeon and analogous results are observed. Pinch the toes and there is an effort to remove the foot. Pass a lighted candle in front of it, and the head follows its motion. Discharge a pistol, and the eyes are opened and other evidences given that the sound is heard, or rather makes its proper impression on the nerves, but excites no emotion. Referring to this experiment, Dr. Maudsley says: "It is quite evident from this experiment that general sensibility and special sensations are possible after the removal of the hemispheres; but they are not then transformed into ideas. The impressions of sense reach and affect the sensory centres, but they are not intellectually perceived; and the
the attempt to explain it is an idle act. "The search for light behind the light," he avers, is the natural illusion of reason-the will o' wisp of philosophy." Problems of Life and Mind, Vol. I, p. 163. EDITORS.]
proper movements are excited, but these are reflex or automatic."*
If, notwitstanding these facts, any one chooses to assert that mind is a distinct power, or existence, apart from the physical organism—an existence, however, which can neither know itself nor manifest itself, except through physical energiesit is not possible, as yet, to demonstrate his error, except on the plane of the knowable. But the hypothesis is opposed to every principle of sound reasoning-to every principle which is recognized of binding force in other departments of knowledge. Sir William Hamilton, who was certainly conservative enough, from a theological stand-point, in his methods and results, lays down, as the fundamental principle of sound reasoning, that, in explaining any phenomena, we have no right to assume more causes than are necessary, or, where known causes suffice, we have no right to invent new ones. Now, we have, in the physical energies connected with the nervous organism, a cause which the most eminent physiologists hold to be adequate to explain, so far as explanation is possible, all mental phenomena. We certainly have, in these physical energies, an invariable accompaniment of mental activity—an accompaniment exactly proportioned to this activity. This is the only evidence we have of a causal connection in any case; and it is certainly as easy and as rational to believe that consciousness and thought are direct results of cerebral action, or the recognition by cerebral forces of their own activity, as it is to believe this activity essential to enable the brain to think; and one or the other is certainly true, for, so far as we know mind at all—that is, the principle of intelligence we know it only in connection with cerebral action.
Unless it can be shown, therefore, that the hypothesis of a common basis for mind and matter involves a contradiction, or inconceivable conditions, it is logically irresistible. This is attempted, and it is the only objection which has ever been urged, aside from the necessity of an individual soul to maintain our personal immortality, in the statement that mental qualities are so entirely different from physical qualities, that *Body and Mind, pp. 20-21.
thought and volition are so absolutely distinct from form, color, weight, etc., that we cannot conceive, to adopt philosophical language, the two sets of attributes inhering in the same substance. Whatever force there might be in this objection is, however, utterly destroyed when you abandon the old notion of the objective existence of the physical qualities of matter as such. As we have seen, we know matter only as an objective cause of sensation-as power, energy. The various physical qualities, as we conceive them, are altogether the product of thought-the knowledge of sensations. Atoms, which are assumed as the vehicle of these forces, have no more real existence than the old metaphysical "entities" which modern scientists so much deride. Ex hypothesi, if they existed, we could not know it, as it is the forces only that centre in them which exert any influence. And these forces are certainly as appropriate an explanation of mental as of physical phenomena. Or, to reverse the statement: invent what explanation you like for mental phenomena, and the same cause will account for physical qualities.
This is a legitimate corollary from the approved teaching of the best scientific authorities, and it is not inconsistent with the most profound philosophical speculation. It affords, we believe, a broad neutral ground on which the contending hosts of science and metaphysics may meet and embrace. Professor Tyndall's celebrated declaration, in his Belfast Address, that he discovered in matter "the promise and potency of every form of life," is chiefly objectionable to timid and conservative people from the form of the expression. If he had said, what doubtless he would accept as substantially equivalent, that the same power which manifests itself in the forces of inorganic nature is concerned in the production of all forms of life, and that these forms equally with those forces are the unfolding of a Being, from everlasting to everlasting the same, and whose activity, under similar circumstances, is invariable-if he had put his thought in some such form as this, there are many of the most profound theologians who would accept it without qualification.
Professor Huxley, however, is perhaps the most prominent
scientist who has risen above what may be called the mere physical view of nature. "The more completely," he says, "the materialistic proposition is admitted, the easier it is to show that the idealistic position is unassailable, if the idealist confines himself within the limits of positive knowledge.'
On the other hand, among modern philosophical writers the idealist hypothesis meets almost unanimous approval. J. Stuart Mill defines matter as a "permanent possibility of sensation," that is the power which causes the phenomena we call physical. Herbert Spencer adopts substantially the same view. Almost without exception the profoundest thinkers of the age, whether physicists or metaphysicians, concede that we know matter only as the power which manifests itself in physical phenomena, and mind as the power concerned in consciousness and its attendant phenomena. It remains only to connect the two, and strive to attain some faint but just conception of the character and attributes of this power which is concerned in all existence, or rather, which is all existence, and which manifests itself in all phenomena, whether physical or mental.
Whether you choose to call this power mind or matter, God or nature, is of no consequence. All we know of it is as it reveals itself in consciousness, through natural phenomena-as force. This is the only agent recognized by science; it is the only power revealed in nature. If there is anything beyond this, if there is any power in the universe save that which can be measured thermometrically, or recognized in the molecules of matter, it has not been discovered; phenomena do not require it; science does not regard it. As force only is this power revealed in the heavens or on the earth, in mind or in matter; as force only can it be apprehended in thought. The attributes of force are the attributes of God.
Now, what are these attributes? The only force of which we have immediate knowledge-that revealed in consciousness -is indissolubly connected with a nervous organization, and is endowed with consciousness and intelligence. Are these qualities, or conditions, essential to each other? The answer to * English Men of Letters: Hume, pp. 79, 80.